Pallet truck



March 11, 1947. J FRAMHEIN.

PALLET TRUCK Filed Sept. 25, 1943 4 Sheets-S eet 1 INVENTOR .14. J7? M 4mw hm mm ATTORNEY March 11, 1947. H. J. FRAMHEIN PALLET TRUCK FiledSept. 25, 1943 4 Sheets-Sheet 2 v-z, h 464/- BY ATTORNEY March 11, 1947.H. J.'FRAMHEIN PALLET TRUC K Fil ed Sept. 25, 1943 4 Sheets-Sheet 3INVENTOR V F MM ATTORNEY H. J. FRAMHEIN 2,417,396

PALLET TRUCK March 11, 1947.

' 4 Sheets-Sheet 4 Filed Sept. 25, 1943 R 3 R m E V u \m m i w w y W f.m x.. ...L...

w 7.1%; .1 48,; BY 5? r ATTORNEY Patented Mar. 11, 1947 PALLET TRUCKHerbert J. Framhein, Chicago, Ill., assignor to The Yale & TowneManufacturing Company, Stamford, Conn., a corporation of ConnecticutApplication September 25, 1943, Serial No. 503,745

Claims.

This invention relates to industrial lift trucks, and more particularlyto industrial lift trucks of the type shown in my application Serial No.458,035 filed September 11, 1942. In that application I disclose a basicimprovement in industrial trucks of the type adapted for cooperationwith pallets, and more particularly, I disclose new and novel means forfacilitating the entry of the load platform of an industrial truckbetween the floors of a pallet.

In brief, this is accomplished in my invention through the provision ofmeans for maintaining the load lifting wheels at the rear of theelevating platform in an elevated position when the elevating platformis in its fully lowered position. Intermediate wheels are preferablyprovided for supporting the truck for movement when the load liftingwheels are elevated, the lifting of the elevating platform through themovement of the load lifting wheels acting to raise the intermediatewheels so that they will not interfere with the movement of the truck.

Modifications of the invention disclosed in the said application supra,are set forth in my application Serial No. 469,324 filed December 17,1942, and Serial No. 493,701 filed July '7, 1943. In the presentapplication I illustrate a further modification of my invention appliedto trucks of the class in which the lifting wheel links at the rear ofthe elevating platform are actuated by the links pivotally connectingthe forward end of the elevating platform of the truck to the liftinghead. In order to simplify the description of this modification of myinvention I shall show it applied to the trucks of this class disclosedin the Quayle Patent No. 2,274,164 granted February 24, 1942, and in theHastings Patent No. 2,234,925 granted March 11, 1941. A reading of thosepatents will be helpful toward a fuller understanding of this invention.

In brief, the object of my invention disclosed and claimed in thisapplication is the adaptation of a truck of the class indicated forfacilitated cooperation with a pallet.

As one feature of my invention through which the objectives thereof areobtained, the front connecting links between the elevating platform andthe lifting head are adapted to hold the rear.

wheel lifting links in position to maintain the lifting wheels off theground when the elevating platform is in its fully lowered position. Afurther feature of my invention resides in the use of intermediatewheels, preferably secured to the elevating platform, for supporting thetruck for' movement when the elevating platform is lowered and thelifting wheels are off the ground. As a still further feature of myinvention the intermediate wheels are raised off the ground as v thelifting wheels are lowered and the elevating platform is lifted.

I have thus outlined the more important features of my invention inorder that my contribution to the art may be better understood and inorder that the relation of my contribution to the prior art may bebetter comprehended. I do believe that my contribution is a broad andvaluable one and that I am entitled to patent claims that will preventnewcomers in the field from utilizing my contribution to the art withsuch variations in physical structure as will readily occur to thoseskilled in the art. Also, while I have described generally severalimportant features of my invention, there are other important featuresthat will be described particularly in the specification and will beclaimed in the claims appended hereto.

Referring now to the drawings:

Fig. 1 illustrates in vertical partial section a truck to which myinvention is applied.

Fig. 2 is'a perspective view of one of the forward links connecting theelevatingplatform to the lifting head and adapted to actuate the rearlifting wheel links.

Fig. 3 is a view similar to Fig. 1 showing the elevating platform in anelevated position.

Fig. 4 is a plan view of the truck of Figs. 1 and 3.

Fig. 5 is a view similar to Fig. 1 showing a modified form of truck inwhich the elevating platform is pivoted in a somewhat different mannerto the lifting head.

Fig. 6 is a perspective view of the linkage mechanism whereby the rearlifting wheels of the second modification are actuated.

Referring first to Figs 1-4, the lifting head of the truck is designatedby reference numeral l0 and is shown supported by a steering head IIhaving a steering wheel l2. A hydraulic pump is designated by referencenumeral l3 and is actuated by a treadle I4. A release treadle l5 for thehydraulic pump I3 is adapted to control the lowering movement of theelevating platform as will hereinafter be set forth.

The elevating platform is designated generally by reference numeral l6and is of the U type.

having a pair of legs each designated by reference numeral [1. Theforward end of the elevating platform I6 is in the form of a verticalstandard l8 that is pivotally connected to a vertical standard [9 of thelifting head ID. The connection is made at the upper end of theelevating platform standard is through a pair of links 23 pivoted to thelifting head standard l9 at 2|, and

to the elevating platform standard at 22.

The lower end of the elevating platform standard i8 is pivoted to thelower end of the lifting I8 of the lifting platform i6 has at each sidea pair of brackets 25 on which is mounted a shaft 26, each link 23 beingpivotally supported on the standard 18 through one of the shafts '26 Thel forward end of each link 23 is' supported reiag tively to the liftinghead by a shaft 27 secured at each end by a nut 28 relatively to thesaid 1 links 23. It is now readily seen that the-elevat-- ing platformmay be swung through upper links 29 and lower parallel links 23relatively to the lifting head so as to be elevated relatively thereto.

The lifting of the front end of the elevating platform it on the upperand lower links is acpivoted at its lower end at 31 on the lifting head,

' and at 32 relatively to the standard It. The rear end of the elevatingplatform It is adapted for lifting movement simultaneously with theforward end, this action being accomplished by the pivotal movement ofthe rear wheel lifting links 35 complished by the hydraulic ram assembly39 i pivoted at 36 to each of the legs 11 of the elevating platform I6Each link carries a lifting wheel 31 and is pivoted at 38 to a tensionrod 39 that extends forwardly, and as best shown inFig. 3

is pivoted at '43 to one of the links 23.

" In the usual type of truck as disclosed in the Quayle patent, when theelevating platform is in its lowered position of Fig, 1, the links 23;rods 39 and lifting wheel links 3 5 are positioned so that the wheels 3?are against the ground G.

' In such trucks it is relatively difficult to move the elevatingplatform into position between the boards at of a paint P shown in Fig.1, and numerous eirpe'dients have been suggested. In my truck, thearrangement of the parts is such that when the elevating platform is inits fully lowered position of Fig. 1, the rear lifting wheels .31 areheld up and away from the ground as illustrated. This action is madepossible by the particular novelarrangement of the rear wheel liftinglinks 35, the rods 39 and the links 23relatively to one another, all asis clearly shown in my drawings.

For pressing the elevating platform into its position of Fig. 1; thatis, into its fully lowered position, I utilize a pair of springs 45.Each of these springs 45 is mounted about a shaft 46 that through thebifurcated shackle 4'! is secured at 48 to the elevating platform 16.Each spring 45 presses at its lower end against a disk 59 adjustablysecured by nuts 51! to the rods 18. At its upperend eachspring d5presses against the lifti'n'g head through the medium of a roundedwasher from the elevating platform.v

preferably one wheel at each side of the truck.

form is in its fully lowered position and is maintained in that positionby the springs 45. The links 23 in cooperation with rods '39 hold therearwheel lifting links 35 in position maintaim. ing the lifting wheels37 off the ground. The truck is therefore very easily moved intoposition with its load platform between the floors of the pallet P.

Operation of the lifting treadle it of pump l3 effects the actuation ofthe lifting ram assembly st to Hit the elevating platform throughswinging movement thereof on, upper links 26 and'lower links 23. Thedisposition of the parts is such that the links 255 will first impelswift movement of the rear wheel lifting links 35 toward the position ofFig. 3. This will of course act to lift the rear end of the elevatingplatform as the forward end is lifted by the rain of assembly 30. Itwill also act to lift the intermediate wheels 55 off the ground whilecontinuing the upward movement of the elevating platform at its frontand rear ends. The final lifted position of the elevating platform is ofcourse illustrated in Fig; 3. There, the intermediate wheels are off theground, and lifting wheels 3? are fully down and holdthe rear end of theelevating platforrri fully lifted. 7

If the release treadle [*5 is now depressed, the elevating platform willbe lowered under the influence of the load'and the springs 55. Loweringmovement of the elevating platform will of course effect the lifting ofthe wheels 31' off the ground and the bringing of the intermediatewheels 55 against the ground'as in Fig; 1. I believe that from the briefdescription herein given; the operation of this modification of myinvention will be clearly understood. Naturally, a fuller understandingof the invention will be possible after a reading of the specificationsof my earlier applications referred to above, and possibly a reading ofthe Quayle patent.

In Fig. 5 I show a modification of my invention utilizings'ubstantiallythe arrangement of the parts illustrated in Figs. 1%. However, uh likethe truck of my first modification, the 'ele vating platform of 5extends forwardly relatively to the liftinghead so that the connectinglinks between the lifting head and elevating platform are secured attheir forward ends to the 'ele vat'ing platform and at their rear endsto the lifting head. Thus,'upper links 50 are pivoted at 6|" to theelevating platform and extend rearwardly and are pivoted at 62 to thelifting head. Similarly, the Iowerimks 83, best shown in Fig; 6, arepivoted at their forward ends through shafts of to the elevatingplatform. The links then extend 're'arwardly and are pivoted through ashaft 65 to the lifting head 66, the lifting head provided with thesleeve 6? for the passage of the shaft 65, I

The rods extendingfrom the rear wheel lifting links :68 are designatedby reference numerals 69 and take the place of rods 33 oftne first modi-U shaped member II are through stub shafts '13 secured to the links 63for actuation by the said links, all as clearly seen in Fig. 6. In thefull line position of the parts in Fig. 5, the elevating platform islowered and the intermediate wheels 55 are against the ground. The lowerconnecting links 63, through the U member TI and the rods 69, hold therear wheel lifting links 68 so that the lifting Wheels 3'! aremaintained spaced from the ground as in the first modification. In thedash and dotted line position of the parts, the elevating platform isshown in its lifted position. The forward end of the platform movesupwardly and rearwardly to the lifted position, with the links 60 and 63moving as shown to their dash and dotted line positions. The U member 7!is actuated by links 63 and through rodstii swings the lifting links 68downwardly, thus lifting the rear end of the elevating platform. Thoseskilled in the art will of course now fully appreciate the operation ofthe second modification of my in- Vention.

I now claim:

1. In a lift truck of the class described, a wheel supported liftinghead, an elevating platform, connecting links pivotally connecting theforward end ofsaid platform to said lifting head, lifting means forlifting the front end of said elevating platform relatively to saidlifting head through swinging movement thereof on said links,intermediate wheels on said elevating platform contacting the ground forsupporting said platform when it is in its lowered position relativelyto said lifting head, lifting wheel links pivoted to the rear of saidelevating platform, lifting wheels on the said lifting wheel linksadapted to contazt the ground to lift the rear end of said elevatingplatform as said liftingv wheel links swing downwardly relatively tosaid platform, means of connection so connecting said lifting wheellinks and said connecting links that said connecting links hold saidlifting Wheel links in position to maintain said lifting Wheels off theground and with the plane of the lowermost portions of their peripheriesabove the plane of corresponding portions of the peripheries of saidintermediate wheels when said elevating platform is in its fully loweredposition relatively to the ground and said lifting head, the swinging ofsaid connecting links incidental to the lifting of said elevatingplatform by said lifting means acting through said means of connectionto swing the lifting wheel links downwardly to lift the rear of saidelevating platform.

2. In a lift truck of the class described, a wheel supported liftinghead, an elevating platform, connecting links pivotally connecting theforward end of said platform to said lifting head, lifting means forlifting the front end of said elevating platform relatively to saidlifting head through swinging movement thereof on said links,intermediate wheels for supporting said elevating platform for movementon the ground when it is in its fully lowered position relatively tosaid lifting head, lifting wheel links pivoted to the rear of saidelevating platform, lifting wheels on the said lifting wheel linksadapted to contact the ground to lift the rear end of said elevatingplatform as said lifting wheel links swing, downwardly relatively tosaid platform, means of connection so connecting said lifting wheellinks and said connecting links that said connecting links hold saidlifting wheel links in position to maintain said lifting wheels off theground and with the plane of the lowermost portions of their peripheriesabove the plane of corresponding portions of the peripheries of said.intermediate wheels when said elevating platform is in its fullylowered position relatively to the ground and said lifting head, theswinging of said connecting links incidental to the lifting of saidelevating platform acting through said means of connection to swing thelifting wheel links downwardly to lift the rear of said elevatingplatform.

3. In a lift truck of :the class described, a wheel supported liftinghead, an elevating platform, connecting links pivotally connecting theforward end of said platform to said lifting head, lifting means forlifting the front end of said ele-, vating platform relatively to saidlifting head through swinging movement thereof on said links,intermediate wheels on said elevating platform contacting the ground forsupporting said platform when it is in its lowered position relativelyto said lifting head, lifting wheel links pivoted to the rear of saidelevating platform, lifting wheels on said lifting wheel links adaptedto contact the ground to lift the rear end of said elevating platform assaid lifting wheel links swing downwardly relatively to said platform,rods so securing said lifting wheel links and said connecting links thatsaid connecting links hold said lifting wheel links in position tomaintain said lifting wheels off the ground and with the plane of thelowermost portions of their peripheries above the plane of correspondingportions of the peripheries of said iiitermediate wheels when saidelevating platform is in its fully lowered position relatively to theground and said lifting head, the swinging of said connecting linksincidental to the lifting of said elevating platform acting through saidrods to swing the lifting links downwardly to lift the rear of saidelevating platform.

4. In a lift truck of the class described, a lifting head having avertical standard, an elevating platform having a vertical standard atits forward end, connecting links pivotally connecting the standard ofsaid platform to the vertical standard of said lifting head, liftingmeans for lifting the front end of said elevating platform relatively tosaid lifting head through swinging movement thereof on said connectinglinks, intermediate wheels on said elevating platform contacting theground for supporting said platform when it is in its lowered positionrelatively to said lifting head, lifting Wheel links pivoted to the rearof said elevating platform, lifting wheels on the said lifting wheellinks adapted to contact the ground to lift the rear end of saidelevating platform as said lifting wheel links swing downwardlyrelatively to said platform, means of connection so connecting saidlifting wheel links and said connecting links that said connecting linkshold said lifting wheel links in position to maintain said liftingwheels off the ground and with the plane of the lowermost portions oftheir peripheries above the plane of corresponding portions of theperipheries of said intermediate Wheels when said elevating platform isin its fully lowered position relatively to the ground and said liftinghead, the swinging of said connecting links incidental to the lifting ofsaid elevating platform acting through said means of connection to swingthe lifting links downwardly to lift the rear of said elevatingplatform.

5. In a lift truck of the class described, a wheel supported liftinghead having a vertical standard, an elevating platform having a verticalstandard at its forward end, connecting links pivotally connecting thestandard of said platform aeimao through swinging movement thereof onsaid links,

lifting wheel links pivoted to the rear of said elevating platform,lifting wheels on the said lifting wheel links adapted to liftthe rearend of said elevating platform as said lifting wheel links swingdownwardly relatively to said platform, means of connection soconnecting said lifting wheel links and said connecting links that saidconnecting links hold said lifting wheel links in a retracted positionrelatively to said elevating platform to maintain said lifting wheels Ioff the ground when said elevating platform is in its fully loweredposition, the swinging of said connecting links incidental to thelifting of said elevating platform acting through said means ofconnection to swing the lifting links downwardly to lift the rear ofsaid elevating platform, and intermediate wheels on said elevatingplatform having their peripheries below the peripheries of said liftingwheels when said lifting links are retracted relatively to saidelevating platform, whereby said intermediate wheels contact the groundto support said platform when it is in its lowered position with saidlifting wheels raised off the ground.

6. Ina lift truck of the class described, a wheel supported liftinghead, an elevating platform, connecting links pivotally connecting thefor ward end of said platform to said lifting head, lifting means forlifting the front end of said elevating platform relatively to saidlifting head.

ing the elevating platform for movement when it 1 is in its fullylowered position relatively to said lifting head, lifting wheel linkspivoted to the rear of said elevating platform, lifting wheels on thesaid lifting wheel links adapted tocontact the ground to lift the rearend of said elevating platform as said lifting wheel links swingdownwardly relatively to said platform, means of connection soconnecting said lifting wheel links and said connecting links wherebysaid connecting links hold said lifting wheel links in position tomaintain said lifting wheels off the ground and with the plane of thelowermost portions of their peripheries above the planeof correspondingportions of the peripheries of said intermediate wheels when saidelevating platform is in its fully lowered position relatively to theground and said lifting head, the swinging of said connecting linksincidental to the lifting of said elevating platform acting through saidmeans of connection to swing the lifting wheel links downwardly to liftthe rear of said elevating platform.

'7. In a lift truck of the class described, a wheel supported liftinghead having a vertical standthrough swinging movement thereof on saidlinks, spring means pressing said elevating platform into,

its fully lowered position relatively to said lifting head, liftingwheel links pivoted to the rear of said elevating platform, liftingwheels on the said lifting wheel links adapted to lift the rear end ofsaid elevating platform as said lifting wheel links swing downwardlyrelatively to said platform, means of connection so connecting saidlifting wheel links and said connecting'links that said connecting linkshold said lifting wheel links in a retracted position relatively to saidele'vat, ing platform to maintain said lifting wheelsofi the ground whensaid elevating platform is in 1ts fully lowered position relatively tothe ground and said lifting head, the swinging of said connecting linksincidental to the lifting of said elevating platform acting through saidmeans of connection to swing the lifting links downwardly to lift therear of said elevating platform, and intermediate wheels on saidelevating platform having their peripheries below. the peripheries ofsaid lifting wheels when said lifting links'are retracted relatively tosaid elevating platform, whereby said intermediate wheels contact theground to support said platform when itlis in its lowered position withsaid lifting wheels raised off the ground. a I

8. In a lift truck of the class described, a wheel supported liftinghead, an elevating platform, connecting links pivotally connecting theforward end of said platform'to said lifting head, said links beingpivoted at their rear ends to the lifting head, and at their forwardends to the elevating platform, lifting means on said lifting headadapted to lift the front end of said elevating platform relatively tosaid lifting head through swinging movement thereof rearwardly andupwardly on said links, intermediate wheels on said elevating platformcontacting the ground for supporting said platform when it is in itslowered position relatively to said lifting head, lifting wheel linkspivoted to the rear of said elevating platform, lifting wheels on thesaid lifting wheel links adapted to contact the ground to lift the rearend of said elevating platform as said lifting wheel links swingdownwardly relatively tosaid platform, rods connecting said liftingwheel links and said connecting links whereby said connecting links holdsaid lifting wheel links intion. to maintain said lifting wheels off theground and with the plane of the lowermost portions of their peripheriesabove'the plane of corresponding portions of the peripheries of saidintermediate wheels when saidelevating platform is in its fully loweredposition relatively to the ground and said lifting head, the swinging ofsaid connecting links incidental to the lifting of said elevatingplatform acting through said rods to swing the lifting wheel linksdownwardly to lift the rear of said elevating platform. 7 l 9. In a lifttruck of the class described, a lifting head, an elevating platform,connecting links pivotally connecting the forward end of said platformto said'lifting head, lifting means adapted to lift the front end ofsaid elevating platform relativelyto said lifting head through swingingmovement thereof on said links, lifting wheel. links pivoted. to therear of said elevating platform, lifting wheels on the saidlifting'wheel links adapted to lift the rear endof said elevatingplatform as said lifting wheel linkssw'rng downwardly relatively to saidplatform, means connecting said lifting wheel links and said con--,

necting links so that said connecting links hold said lifting wheellinks in a retracted position relatively to said elevating platform tomaintain said lifting wheels off the ground when sai'delevatingplatformis in its fully lowered position relatively to the ground and saidlifting head, the swinging of said connecting links incidentalto thelifting of said elevating "platform acting;

through said means of connection to swing the lifting links downwardlyto lift the rear of said elevating platform, and intermediate wheelspositioned with their peripheries below said lifting wheels when saidlifting links are in said retracted position for supporting said truckwhen said platform is in its lowered position relatively to said liftinghead with said lifting wheels raised off the ground.

10. In a lift truck of the class described, a lifting head, an elevatingplatform, connecting links pivotally connecting the forward end of saidplatform to said lifting head, lifting means for lifting the front endof said elevating platform relatively to said lifting head throughswinging movement thereof on said links, intermediate wheels on saidelevating platform contacting the ground for supporting said platformwhen it is in its lowered position relatively to said lifting head,lifting wheel links pivoted to the rear of said elevating platform,lifting wheels on the said lifting wheel links adapted to lift the rearend of said elevating platform as said lifting wheel links swingdownwardly relatively to said platform, a U member pivoted at each legof its U form to one of said connecting links, means connecting saidlifting wheel links to said U member arranged so that said connectinglinks through said U member hold said lifting wheel links in a retractedposition to maintain said lifting wheels off the ground and with theplane of the lower most portions of their peripheries above the plane ofcorresponding portions of the peripheries of said intermediate wheelswhen said elevating platform is in its fully lowered position relativelyto the ground and said lifting head, the swinging of said connectinglinks incidental to the lifting of said elevating platform actingthrough said U member and connecting means to swing the lifting wheellinks downwardly to lift the rear of said elevating platform.

- HERBERT J. FRAMHEIN.

REFERENCES CITED The following references are of record in th file ofthis patent: v

UNITED STATES PATENTS Number Name Date 2,361,544 Hastings 0st. 31, 19442,358,957 Barrett Sept. 26, 1944 2,274,164 Quayle Feb. 24, 19422,110,424 Quayle Mar. 8, 1938

